X-ray films, when prepared for exposure, are stored in light-tight film holders, kept closed by a vacuum prevailing inside of the film holder combined with external atmospheric pressure prevailing outside the film holder. Such film holders are well known in the art. Such film holders are more fully disclosed in my patent application Ser. No. 343,982, filed Mar. 22, 1973 for VACUUM FILM HOLDER FOR RADIOGRAPHY, now abandoned.
This invention refers more particularly to means for opening and closing vacuum X-ray film holders. It is common practice to use for this purpose means defining chambers for receiving the film holders for X-ray films. Such chambers are provided with means for selectively establishing therein a vacuum or atmospheric pressure. Such chambers are further provided with means operable from the outside of the chamber in the presence of a vacuum therein for performing some mechanical operation inside of the chamber. Prior art devices of this kind generally include a bushing for mechanical, hydraulic or pneumatic means projecting through one of the chamber-forming walls, operable from the outside of the chamber by a manipulator for actuation of a film holder inside of the chamber. These prior art devices are relatively complex and the aforementioned bushings thereof are an undesirable feature, their fluid-tightness never being fully assured. Furthermore, the aforementioned prior art devices do not lend themselves to form part of automated film-change and film-processing systems.
The object of the present invention is to provide improved devices for opening and closing vacuum X-ray film holders which devices are not subject to the drawbacks and limitations of the aforementioned prior art devices.